Steam circulating system



July 31, 1934. A REISS ET AL 1,968,171

STEAM CfRCULATING SYSTEM Filed Sept 30, 193 2 Sheets-Sheet 1 as. 1 M .56a I I i 10 3/ M I 71 i I f Gus/ m G7WYWWS July 31, 1934. A, REES Er AL1,968,171

STEAM CIRCULATING SYSTEM Filed Sept. 30, 1932 2 Sheets-Sheet 2 -1Z'.5.545/ 89 r 51 f 111 1 1 :I: 'P" I II 15 IE E I 1, (11 1.; 3111 '76 ?P nsPatented July 31, 1934 UNITED STATES PATENT" OFFICE Joseph Peter.Christ, Niederrad, Germany Frankfort-on-the-Main- Application September30, 1932, Serial No. 635,684 In Germany December 3, 1931 7 Claims.

Steam circulating systems are known in which the steam .consumingapparatus is connected in parallel with the main steam conduit and atthe same time each .steam consuming apparatus 6 is provided with a steamseparator, the steam separators being connected by a common conduit forthe condensate as well as by a common conduit for the steam. The steamobtained in the steam separators is passed by way of a throttle 10arrangement to a common conduit which discharges in the steam space of acommon device for tapping off the water of condensation. In this way itis possible to attain only an incomplete utilization of the heat of thesteam and in particular that heat present in the water in the lastcommon steam separator is not utilized because this water is underpressure and thus contains large quantities of heat.

The subject matter of the present invention is a steam circulatingsystem in which this disadvantage is avoided in that the steam consumingapparatus is divided into three groups, one of which is supplieddirectly with heating steam, the second group is supplied with mixedsteam which is composed of the heating steam and the waste steam fromthe water separators of the first and second groups. The third groupreceives steam solely from the water separator of the mixed steam group,the actual exhaust steam of this suction steam group being againsupplied to the corresponding steam consumers.

In this way the heat of the steam is utilized to a considerable extentand it is attained that in the last steam separator in which the entirecondensed water collects there is a reduced pressure which results in asubsequent release of steam from the water so that here also a largepart of the heat is again introduced into the cycle.

At the same time care is taken that the suction pressure of therequisite apparatus for circulating the steam remains the same. This isattained in that the control of quantity is not effected by regulatingthis apparatus effecting the circulation of the steam but by regulatingan additional jet which is provided in the conduit beyond the diffuserof the said apparatus. This additional jet also exerts a suction actionon the apparatus so that the performance of the 5 latter is in this waystill further increased.

As the suction action in the steam separators of the mixed steam groupand of the suction group is comparatively small, the non-return valvesprovided .over these separators operate only unreliably and they alsofrequently constitute a resistance which influences the suction action.For this reason this check valve is according to the inventionautomatically controlled by the pressure difference between the pressurein the conduit and the pressure in the suction conduit. The control ofthe non-return valve may be effected by a membrane or a piston, thehousing or cylinder of which is connected on one side with the pressureconduit and on the other side with the suction conduit.

The individual steam consumers of the different groups can also besubdivided into sub-groups connected in parallel. At the same time thesesub-groups of the mixed steam group for example can be subjected to afurther subdivision in that certain of these groups are combined andinterconnected in parallel. The remaining arrangement is not affectedthereby.

Two embodiments of the invention are shown by way of example in theaccompanying drawings in which Fig. 1 shows a system in which only onesteam consumer is present in each group. I

Fig. 2 shows on a larger scale the corresponding steam circulatingapparatus with an auxiliary jet positioned in front thereof and with.control non-return valve for the steam separator.

Fig. 3 shows a system with multiple group subdivision.

Fig. 4 shows diagrammatically a further embodiment of the invention inwhich the heating step and the suction step are each subdivided into twosubordinate groups.

Fig. 5 shows diagrammatically a further subdivision, as adapted forusein heating the cylinders of a paper machine[ Referring to Figs. 1 and2, 1 isthe steam consumer of the heating steam group and may be-aradiator, a cylinder of a steam-heated papermachine, a cookingevaporating or drying apparatus or the like; This steam consumer issupplied with heating steam through the conduit 2 either directly withlive steam or with intermediate steam or exhaust steam from a steamengine, turbine or the like. The lower end of the steam consumer isconnected with the steam separator 3 the water of condensation fromwhich is passed at 4 to a common conduit 5 which discharges into thelast steam separator 6 of the entire system. p

The mixed steam group comprises the steam consumer 7 which at its lowerend at 8 is connected with the steam separator 9 which in turn passesthe condensed water into the common conduit 5 at 9a and thus into thewater space of the steam separator 6. The steam consumer 7 is connectedto the steam circulating apparatus 10 the suction conduit 11 of which isconnected with the steam space of the steam separator 9. Live steam isfed into the circulating apparatus at 12 from the live steam conduit 2for example.

A conduit 13 which leads from the steam space of the steam separator 3of the heating steam group also discharges into the steam space of thesteam separator 9 01 the mixed steam group. A throttle may be providedin this conduit at 14.

The steam circulating apparatus 10 is constructed as shown in Fig. 2.Beyond the jet 14 in the subsequent diffuser 15 is a second jet 16 whichis connected by means of the conduit 17 with the pipe 12 branching fromthe heating steam conduit. The regulating device 18 of the steamcirculating apparatus 10 is set once and for all to a minimumconsumption. The actual re lation of the quantity which is requisite atany time is eiiected by means of the valve 19 which is provided in theconduit 17 leading to the auxiliary jet 16. In this way the suctionaction in the conduit 11 is not detrimentally affected by the regulationof the quantity.

The third group, Fig. 1, is the suction steam group, the steam consumerof which is indicated by 20. It is connected to a steam circulatingapparatus 21 which is also provided with an auxiliary jet at 22.Pressure is applied to this steam circulating apparatus through theconduit 23 which is connected at 24 to the exhaust steam conduit of thesteam separator 9 of the mixed steam group. Thus the steam circulatingapparatus 21 is operated solely by the waste steam of the two othergroups. The steam consumer 20 is connected by means of the pipe 25 tothe steam separator 6 the steam space of which is connected with thesteam circulating apparatus 21 by the conduit 26. The entire water ofcondensation is removed from the steam separator 6 at 27.

The steam separator 9 as well as the steam separator 6 are each providedin known manner with a non-return valve as shown in Fig. 2 at 28; thestem 29 of this valve is connected with a membrane 30. The membrane 30is enclosed in a housing 31 which above the membraneis connected bymeans of the conduit 32 with the suction space of the correspondingsteam circulating apparatus 10 whereas the space beneath the membrane 30is connected by way of the conduit 33 with the pressure conduit whichleads to the corresponding steam consumer. In this way in consequence ofthe pressure difl'erence on the two sides of the membrane the valve ismaintained open in the presence of a pressure difference whereas itcloses again immediately it this pressure difierence ceases or if itfalls below a definite magnitude.

The steam separator 6 also has a similar positively controllednon-return valve the housing of which is indicated at 34 in Fig. 1.

Now the mode of operation of the arrangement is as follows:

The live steam or heating steam is supplied through the conduit 2 to thesteam consumer 1 and then passes into the steam separator 3 so that thewater which is precipitated passes by way of 4 into the common returnconduit 5 to the water space of the steam separator 6; The separatedsteam passes through the pipe 13 into the steam space of the steamseparator 9 of the second mixed steam group, the steam consumer 7 ofwhich is connected to the steam circulating apapparatus 21 of thesuction group and here is fed to the steam consumer 20, the waste steamand waste water from which pass to the steam separator 6; the apparatus21 then draws of! steam from the separator pipe through the pipe 26 andproduces a certain reduced pressure in the space 6 which causes asubsequent evaporation of the condensate which is contained therein andwhich was collected from all the steam separators.

In this way the entire heat of the steam is almost completely utilized.

In the embodiment according to Fig. 3 individual steam consumers 1 areprovided in-the heating steam group 1 and are connected in parallel witheach other to the heating steam conduit 2 and at the other end are alsoconected in parallel to a common return conduit 35 which leads to thesteam' separator 3 which is connected with the water return-fiow conduit5.

The mixed steam group of this arrangement consists of two-sub-groups,the steam consumers of which are indicated by 36 and 37. The mixed steamis supplied through the conduit 38 to both sub-groups from the steamcirculating apparatus 10 which corresponds to the equivalent apparatus10 in the system of Fig. 1. The one-sub-group 36 of this mixed steamgroup is moreover connected to the common conduit 39 which leads to thesteam separator 40 whereas the other subgroup 37 is connected to thesteam separator 42 by the conduit 41. The steam space of the separator40 is connected with the larger steam separator 42 by means of theconduit 43. Suction steam both from the steam separator 3 and also fromthe steam separator 40 is fed to the steam separator 42 and then passthrough the tube 11 to the steam circulating apparatus 10. As in thesystem of Fig. 1 a pipe 23 branches from the steam separator 42 andleads to the steam circulating apparatus of the suction steam groupwhich is represented by the steam consumers 46 and 47. By means of thepipe 48 the consumers 46 and 47 are connected in parallel to thepressure side of the steam circulating apparatus 21. The return flowoccurs through the conduit 49 to the steam separator 50 in which thecommon water return 'flow conduit 5 also discharges.

The mode of operation of this system is precisely the same as that ofthe system of Fig. 1.

The additional jets and the controlled nonreturn valves are alsoprovided in the system according to Fig. 3.-

The present invention relates further to an improvement or developmentof the steam circulating system. In particular according to the presentinvention the subdivision of the individual groups and stages in thesub-groups is carried out to a greater extent and, in such manner thatthe waste steam of each sub-group is added to the heating steam stage ofthe steam circulating apparatus of the subsequent stages as workingsteam or suction steam. Thus for example the heating steam stage isdivided into two subgroups to which steam is supplied separately fromthe heating steam pipe and from which the condensate is tapped ofiseparately. For each sub-group a steam separator is provided andtheseparated steam oi the group is fed to the steam circulating apparatusoithe third stage, i. e., the

suction steam stage as working steam, whereas the separated steam of thesecond sub-group is drawn in by means of the steam circulating apparatusof the second stage (mixed steam group).

The suction steam stage is also divided into two sub-groups of which oneis attached to the steam circulating apparatus which draws in the steamfrom the steam separator oi the mixed steam stage whereas the wastesteam of this first group of the suction steam stage is fed to the steamcirculating apparatus for the second subgroup of this stage as workingsteam. I

Also the arrangement can further be so modifled that in addition to itsown steam separator each sub-group is also furnished with its own steamcirculating apparatus (injector or any pump member).

By this arrangement the circulation of the steam and thus the eiliciencyof the entire apparatus is further improved. In particular thisextensive sub-division is appropriate ifit is a case of heating a largenumber or heating members step by step one after the other withincreasing yield of heat as is the case for example in the cylinders ofa paper machine.

In the embodiment of Fig. 4 the heating bodies of the heating steamstage are divided into two sub-groups 51 and 52 which are connected tothe heating steam pipe 55 by the pipes 53 and 54. A steam separator 56or 57 is provided for each subgroup and is connected by the commoncondensate return pipe 58 to a condensate collecting vessel 59 which iscommon to all separators of the arrangement.

' The wastesteam oi the steam separator 56 of the first sub-group 51 isfed through the pipe 60 to the steam circulating apparatus 61 of thesuction'steam stage as working steamwhereas the waste steam oi thesecond sub-group 52 of the heating steam stage is drawn in by means 01'the steam circulating apparatus 63 and is fed to the mixed steam group64. This mixed steam stage 64 has in turn the steam separator 65 whichis connected with the steam circulating apparatus 61 by means of thepipe 66.

The suction steam stage is divided into two sub-groups which areindicated by 6'? and 68. The sub-group 67 receives its steam through thepipe 69 from the steam circulating apparatus 61 and its waste steam isfed into the steam separa-.

'- tor 70. The waste steam from this separator passes through the pipe'71 as working steam into the steam circulating apparatus '72 to whichthe second sub-group of the suction steam stage is attached. Thussub-group 68 delivers its waste water through the pipe '13 into thecommon condensate collecting vessel 59 from which the vapour is drawnoff through the pipe '74 into the steam circulating apparatus '72.

The mode of operation is that-the heating steam passing through the pipe55 and the branch pipes 53 and 54 into the two sub-groups 51 and 52,heats the heating bodies of these sub-groups whereupon the waste steamof the two groups passes into the separators 56 and 57 and here depositsits water which is drawn off through the pipe 58 to the commoncondensate collecting vessel 59. Then the waste steam from separator 56passes through pipe 60 to steam circulating apparatus 61 where it isused as working steam, and the exhaust steam from separator 5'1 passesto steam circulating apparatus-63 as suction steam. The subsequentstages are provided with steam separators for each sub-group.

- In the embodiment according to Fig. 5 which represents the arrangementin apaper machine the individual cylinders of the paper machine whichare to be heated are indicated in order with the reference numerals 51',52', 53', 54' and so on up to The heating steam stage comprises thecylinders 68'80' the mixing steam stage the cylinders 58-67' and thesuction steam stage thecylinder 51-57. Separate branch pipes pass fromthe steam pipe '75 to each cylinder 68'80' which are to be heated,whereas three steam separators 76, '77 and "78 are provided by which theheating steam stage is divided into three sub-groups. These three steamseparators are connected to the common condensed water discharge pipe'79 which leads to the condensate collecting vessel 80.

The waste steam from the separators '76 and 'l'l is fed through the pipe81 to the steam circulating apparatus 82 and 83 of the two groups of thesuction steam stage as working steam, whereas the waste steam from theseperator '18 is drawn in by the steam circulating apparatus 84 of themixed steam stage. r

This mixed steam stage is again divided into two groups with which thesteam separators 85 and 86 are associated. The steam separated by 85 isdrawn in through the pipe 87 by the steam circulating apparatus 82 otthe suction steam stage whereas the waste steam from'the separator 86passes through the pipe 88 to the steam circulating apparatus 89 of thesecond group of the mixed steam stage;

The suction steam stage is also divided in two sub-groups of which oneis connected to the sep-. arator 90 and-the other to the separator 91.The waste steam from 90 is fed through the pipe 92 to the steamcirculating apparatus 83 whereas the waste steam from 91 is fed throughthe pipe 93 to the steam circulating apparatus 94 to which the cylinder51' isconnected. These steam separators 86, 85, 90 and 91 are lasoconnected to the common collecting vessel 80 from which the vapour isdrawn 011 through the pipe 95 by the injector 94. v

In this way it is possible to obtain a very good subdivision and gradingof the heat so that a complete utilization of the steam is attained withmost economical consumption and with good and uniform step by stepdrying of the paper.

Instead of providing two subgroups in each stage it is of coursepossible to provide a plural- 13o ity of sub-groups. Each sub-groupwould then be connected with its own steam separator and it-desired alsowith its own steam circulating apparatus (injector'or another steamcirculating pump).

What we claim is:

1. In a steam circulating system, a plurality of steam consumersarranged in three groups, a steam supply conduit, connections with saidconduit for supplying one group with heating steam only, connections forsupplying the second group with mixed steam consisting of heating steamand part of the exhaust steam from the first group, the exhaust steamfrom the firstgroup being sucked into the second group by a steamcirculating apparatus, connections for supplying the third group withexhaust steam from a previous group and with exhaust steam from. thethird group, and vapors from a condensate collecting chamber connectedwith all three groups, the exhaust steam oi the third group and the saidvapors being sucked into the third group by the exhaust steam of theprevious group by means of a circulating apparatus, each group beingprovided with a steam separator connected together by a common conduit.

2. A steam circulating system as claimed in claim 1, in which the steamspace of the steam separator of the first group is connected with thesteam space of the second group and the latter is connected with thesuction space of the steam circulating apparatus of the second group andwith the pressure space of the steam circulating apparatus of the thirdgroup.

3. A steam circulating system as claimed in claim 1, in which the steamspace of the steam separator of the first group is connected with thesteam space of the second group and the latter is connected with thesuction space of the steam circulating apparatus of the second group andwith the pressure space of the steam circulating apparatus of the thirdgroup, the water space of the steam separator of the third groupreceiving condensate from the other separators through said commonconduit, the steam space of the separator of the third group beingconnected by a suction conduit with the suction space ofthe steamcirculating apparatus of the third group.

4. A steam circulating system as claimed in claim 1, in which the steamspace of the steam separator of the first group is connected with thesteam space of the second group and the latter is connected with thesuction space of the steam circulating apparatus 01 the second group andwith the pressure space of the steam circulating apparatus of the thirdgroup, each of said steam circulating apparatuses being provided with adiffuser and an additional jet beyond the diffuser, the connectionssupplying driving steam to the said apparatuses being connected to theadditional jets to control the quantity.

5. A steam circulating system as claimed in claim 1, in which the steamspace 01 the steam separator-oi the first group is connected with thesteam space of the second group and the latter is connected with thesuction spaceof the steam circulating apparatus of the second group andwith the pressure space of the steam circulating apparatus of the thirdgroup, each group being divided into a plurality 0! subgroups connectedin parallel, each subgroup being connected to an individual steamseparator.

6. A steam circulating system as claimed in claim 1, in which the steamspace of the steam separator 01 the first group is connected with thesteam space 01' the second group and the latter is connected with thesuction space of the steam circulating apparatus of the second group andwith the pressure space of the steam circulating apparatus of the thirdgroup, each group being divided into a plurality of subgroups connectedin parallel, each subgroup being connected to an individual steamseparator, the steam spaces of the steam separators of the first andsecond groups being separately connected to a larger steam separator,and a connection between the steam space of said larger separator andthe steam circulating apparatus of the third group through which exhauststeam is drawn to said circulating apparatus.

'7. A steam circulating apparatus according to claim 1 and a connectionbetween the first group of steam consumers and the circulating apparatusof the third group by which exhaust steam of the first group is suppliedto the circulating apparatus of the third group.

AUGUST REISS. JOSEEH PETER CHRIST.

